Project 1: Social and Economic Predictors of Physical and Cognitive Function Functional outcomes such as disability and cognitive impairment critically affect independence and productivity in old age, especially in low-income countries where medical assistance and access to adaptive equipment are limited. However, current surveillance data of disability are extremely limited, and evidence on determinants of functional outcomes in older Africans is heavily dependent on the very few population-based cohorts. There is an urgent need for high-quality data on functional outcomes in adults in sub-Saharan Africa, including both performance-based and self-reported outcomes. Our long term goal is to enrich the INDEPTH cohort studies so they can be used to plan health and social services through the identification of specific, modifiable factors that promote physical and cognitive health of elderly. The overall objective of this project is to introduce validated performance-based and self-reported assessments of physical and cognitive function into three INDEPTH cohorts (in Ghana, Tanzania, and South Africa) and use these data to test whether selected risk factors predict physical or cognitive impairments. This project is tightly integrated with other projects. Functional outcomes and chronic diseases, including cardiometabolic disorders and HIV, are related to Projects 2 and 3 where these disease outcomes are identified. Project 4 uses functional data in analyses of well-being & productivity. Project 1 draws on two waves three years apart for South Africa, and one wave in Ghana and Tanzania; these new surveys will enroll 4000 men and women 50+ in three INDEPTH communities (n=12,000) including all surviving participants from the 2006 SAGE short and long studies. The aims of this project are: AIM 1. To compare the prevalence of physical disability and cognitive impairment using harmonized methods across the three INDEPTH countries. AIM 2. To describe trajectories of mobility and activities of daily living (ADLs) for older adults in South Africa and compare these trajectories to available data on cohorts in Ghana and Tanzania. Here we draw on data from several sources to obtain longitudinal data over a period of 3-7 years. AIM 3. To evaluate social isolation, socioeconomic status, and adult vascular risk factors and HIV as predictors of physical and cognitive impairments and mortality.